Comparative study of direct-measured and calculated LDL in clinical use.

ABSTRACT

OBJECTIVE: Compare DLDL-C and CLDL-C obtained during regular service in hospital. MATERIAL AND METHOD: The study at Bangkok Hospital included 9,285 lipid profiles of different individuals that contained total cholesterol (TC), triglyceride (TG), HDL cholesterol (HDL-C), and directly-measured (by homogeneous method) LDL cholesterol (DLDL-C). The population has mean age 45.92 +/- 12.43 years, 48% were male. LDL-C values were also calculated by Friedewald equation (CLDL-C). However, it was known to have limitation when TG > 400 mg/dL. RESULTS: The DLDL-C is 13.4 +/- 8.8% higher than CLDL-C. The authors could obtain CLDL-C closer to DLDL-C in wider TG range, including other explanatory variables in the equation to calculate LDL-C, by these two equations, DLDL-C = 0.98 TC - 0.84 HDL - 0.12 TG + 0.056 age + 0.071 BMI, and DLDL-C = 0.98 (TC- HDL) - 0.12 TG + 0.1 age + 2.4 sex + 0.2 BMI. CONCLUSION: DM and using lipid-lowering medications had no effect on the correlation of CLCL-C and DLDL-C.